Alnus cordata, the Italian alder, is a tree or shrub species belonging to the familyBetulaceae, and native to the southern Apennine Mountains and the north-eastern mountains of Corsica. It has been introduced in Sicily and Sardinia, and more recently in Central-Northern Italy, other European countries and extra-European countries, where it has become naturalised.
Description
It is a medium-sized tree growing up to tall, with a trunk up to in diameter. The leaves are deciduous but with a very long season in leaf, from April to December in the Northern Hemisphere; they are alternate, cordate, rich glossy green, long, with a finely serrated margin. The slendercylindrical male catkins are pendulous, reddish and up to long; pollination is in early spring, before the leaves emerge. The female catkins are ovoid, when mature in autumn long and broad, dark green to brown, hard, woody, and superficially similar to some conifer cones. The small winged seeds disperse through the winter, leaving the old woody, blackish 'cones' on the tree for up to a year after.
Cultivation
Like other alders, it is able to improve soil fertility through symbiotic nitrogen fixation with the bacteria Actinomyces alni. It thrives on much drier soils than most other alders, and grows rapidly even under very unfavourable circumstances, which renders it extremely valuable for landscape planting on difficult sites such as mining spoil heaps and heavily compacted urban sites. It is commonly grown as a windbreak. Alnus cordata has gained The Royal Horticultural Society's Award of Garden Merit.
Bonsai
The Italian Alder makes a medium to large bonsai, a quick grower it responds well to pruning with branches ramifying well and leaf size reducing quite rapidly.
Other uses
The tree also produces valuable reddish-orange wood. It breaks down rapidly when exposed to air, but is durable when immersed in water. The timber is used for turning and carving, for moulding, furniture, panelling and plywood.
